The present invention relates to a device for storing and converting facsimile communications. More specifically, the present invention makes greater use of a facsimile machine, by storing a facsimile communication which is received.
Facsimile machines are devices for communicating image information between a local machine and a remote machine. Since the original advent of facsimile machines, they have become progressively more sophisticated and complicated. One of the problems that the sophistication has caused is the incompatibility between different generations of facsimile machines, which operate in different facsimile formats. The first generation of facsimile machines is now known as Group I, and is almost completely outdated. A second generation of facsimile machines, called Group II, transmits analog information at a relatively slow pace (approximately six minutes per page). The current (1989) state of the art is known as Group III, and transmits information relatively quickly at approximately 1 page per minute. The information transmitted is in compressed digital form, using a relatively simple compression code (Huffman code and others), and is transmitted having different grades of resolution. By decreasing the resolution, the speed of sending can be increased.
Each time a new generation of facsimile machines has been introduced, it makes obsolete the previous generation of facsimile machines. Many Group III machines currently on the market can operate in Group II or Group III modes, and thereby allow communication with either Group II or Group III machines. Group II machines, however, were never designed for use with Group III and cannot be used with the incompatible Group III format. The Group II machines can not receive and decode nor encode the compressed digital signals produced in Group III.
Group IV facsimile machines are a practical certainty within the next few years. The introduction of Group IV will make the Group III machines obsolete, (or at least less desirable) and many facsimile users will buy a new machine just to get the faster speeds of Group IV.
Many of the currently available Group III machines are extremely sophisticated machines. Some machines have the ability, for instance, to print on plain paper. Moreover, the electronics and auto-dial functions of many of these machines are quite advanced and reliable. However, many people will sell or salvage these machines in their zeal to receive the state of the art Group IV machine.
Moreover, most of the cost of a facsimile machine, especially a complex one as described above, is the scanner and printer etc., while the actual communications electronics represent a less significant part of the cost.
Until the advent of the present invention, no satisfactory way was available for converting from a lower group (eg, Group III) to a higher group (eg, Group IV) in a machine that was not designed for this higher group. The faster transmission speed of the higher group has made it impossible to do a real time conversion between the two groups. I have first realized this problem, and have devised a technique to overcome this problem.
While overcoming this problem, I have also realized that invention enables significant advantages in other types of communications besides facsimile communications, and also provides advantages in facsimile communications other than mere conversion between one group and another. For instance, another problem in facsimile communications is in the field of secure facsimile communications. Secure transmissions involve sending encoded data to a remote facsimile machine. This remote machine cannot receive and print the data without the proper decryption key. The decryption key must always be supervised to maintain its security. Therefore, either an operator must be present with the machine at all times, or the machine is essentially useless during off-hours. If the machine receives the encrypted data without the encryption key therein, it will be received as gibberish. Until the advent of the present invention there has been no satisfactory way of dealing with this problem, and therefore secure facsimile transmission could only be sent during hours when it was known that an operator would be present with the decryption key.
The prior art of facsimile machines has also required that each one facsimile machine be provided for each telephone line, and vice versa. It was impossible to allow one facsimile machine to effectively service two telephone lines, as the facsimile machine would be busy whenever one of the lines was in use. The present invention enables one facsimile machine to service two lines or even more telephone lines.
Moreover, the present invention allows the fastest possible group of facsimile communications to be used, even when the site at which the invention is installed (the local) has only a lower group facsimile machine. This allows savings in the telephone bill, by minimizing the amount of telephone connect time. The present invention also enables time-shift-type sending to minimize the telephone bills by making use of off-peak hours to send the transmission. The time difference to most foreign countries, and notably Japan, is at least a few hours. Therefore, it makes sense to send many communications to these countries during the off-peak hours (typically beginning at 11 p.m. at night). However, this is currently not usually done, because an operator would have to be present to send it. Another aspect of the present invention enables it to be used for just such a purpose.
It is therefore an object of the present invention to provide a facsimile time shifting and converting device which performs all of the above-discussed functions. The device of the present invention enables conversion from any one facsimile group to any other facsimile group now known or later devised. Therefore, any facsimile machine now in use will be compatible with any later facsimile formats via use of the present invention.
Another object of the present invention is to produce a device which time-shifts facsimile information that is received to a later time, to enable it to be properly processed at this later time.
Still another object of the present invention is to time shift facsimile sending until a later time to minimize telephone connect charges.
The present invention overcomes all of these problems in a new and unobvious way. Specifically, the present invention recognizes that all of these problems can be overcome by time shifting the facsimile communications. I have recognized that off-the-shelf audio equipment has a dynamic range which is at least as great as the dynamic range of any standard telephone line. Accordingly, I have recognized that such audio recording technology can be most advantageously used to record any signal from a fax machine. Of course, any other sound recording means or data recording means could be used in place of such audio technology. Once the data is stored on an audio medium, it can be processed as slowly as desired, since the constraints of real-time no longer need to be followed. The conversions of the present invention between groups are therefore done without regard to real time. The tape may be slowed to a half or a quarter its normal speed in order for this conversion to be carried out. Alternately, a circuit may determine certain characteristics from the signal and create an entirely new signal "emulating" the desired group in which to transmit.
The present invention includes means for communicating with a remote facsimile machine, that is sending and receiving the necessary handshaking signals to initiate the remote fax machine to send a message. This message is recorded. It is later played to the local fax machine by emulating a call coming into the local machine and playing back the converted signal.
According to the encryption technique of the present invention, data is detected as being non-standard facsimile format, and is stored on the audio recording means whenever this non-standard format is detected. Alternately, all incoming faxes could be stored to allow playback of any that are later determined after printing to be encoded. Any storage on the storing means initiates an indicator indicating that a reception has been obtained. Upon the user returning with the proper decryption key, the user initiates the storage means to play back the stored information. The stored information is then coupled to the facsimile machine with the decryption key in place, and the facsimile machine recognizes and decrypts the data being played back as though it were the original transmission from the secure facsimile machine. The device of the present invention provides the necessary handshaking signals followed by a playback of the facsimile transmission.
The device of the present invention enables a time-shifting mode in which the telephone number of the receiving facsimile is entered along with a command to wait until a certain time to transmit it. The present invention then stores the facsimile transmission to be sent, on a sound recording means, along with the proper data. At the proper time, the machine of the present invention begins dialing the proper telephone numbers, creates the handshaking signals necessary to communicate with the remote facsimile machine, and finally the recorded information.
The inventor of the present invention discovered another problem in the art resulting from the way in which a fax is usually scanned for transmission. Usually a rectangular sheet of paper is of A4 size or 81/2.times.11 size. There is a shorter edge (e.g., 81/2") that is parallel with the lines of print on the page (in portrait mode), and a longer edge (e g., 11"). These rectangular sheets are scanned via a feeder with the shorter edge of the paper sheet facing the machine. The sheet of paper is scanned along a short axis of the page that is parallel to the short edge such that scanning lines are parallel to the short axis. The scanner typically uses an entire line of scanning elements. Lines of text on the page are scanned in parallel with the lines by either moving the document compared with the scanner or moving the scanner relative to the document.
In some machines, the document is moved relative to the scanner. If the document is inserted in a slightly crooked direction relative to the scanning axis, the scan will be blurred or skewed due to the incorrect scanning angle. In those machines where the document is held stationary, the scan can nonetheless be skewed if its location is less-than-perfectly straight relative to the scanner. Therefore, the scanning quality is dependent on the positioning of the document.
Prior art facsimile machines have used various mechanical structures to maintain the desired orientation. None of these have proved completely satisfactory. Moreover, straightening a crooked document during the scan can actually smear the scanning.
This problem is solved herein by a scanner whereby the paper can be at any desired orientation relative to the scanner. The information is scanned from the randomly-oriented paper and stored as a video image. The image is processed to rotate the image to a proper orientation before sending.
According to this aspect of the invention, the scanner is preferably made longer than usual, so that any orientation of the paper can still be properly scanned.
According to an alternate aspect of the invention, the papers are scanned in the opposite direction to that in which they are normally scanned for fax transmission, with the scan lines parallel to the long axis. For example, an 81/2.times.11 sheet will be scanned in parallel with its 11 inch side. This requires a longer scanner, but enables faster scans. The image may be rotated before sending, so that the receiving fax machine receives the image in a normal orientation. This scanning can occur between 25 and 50% faster because of the longer scan.
Another aspect of this invention scans at a diagonal relative to the page, and uses a point of the page, between two edges, to align the page.
Another aspect of the present invention recognizes that a fax machine is conceptually formed of two basic parts: a facsimile processor that processes the information between the document and the telephone line, and a printer. Typically the printer is one of the more important and expensive parts of the facsimile machine. However, stand-alone facsimile machines usually waste most of their printing capability. Plain paper fax machines include laser print capability, but that laser printing can only be used to print the facsimile (and sometimes to make copies).
According to an improved embodiment of the present invention, the fax machine is a faxing and printing system in which multiple fax processors, and/or printer requests, use a single printer. A print spooler may be used within the facsimile machine to multiplex the various print inputs.
Yet another aspect of the present invention is directed to storage and encoding of faxes. Facsimiles are encoded and transmitted using standard run length algorithms such as Huffman code. A fax can be stored using a graphics format such as a so-called PCX, GIF or TIFF format. Computer-based facsimile machines usually store the sent and received information in this way.
However, these techniques are inefficient for fax storage because the storage technique is not intended for the facsimile environment. The present invention discusses many storage schemes that are intended for facsimiles and optimized for use in facsimile machines. These storage techniques use simple algorithms that compress the information because of their optimization for a fax document. All these compression algorithms are based on the recognition that a facsimile document consists of two parts: large contiguous areas of blank space and large contiguous areas of dark space.
According to yet another aspect of this embodiment, the facsimile machine stores its information before sending, and electronically processes this information to produce a better final image. On the receiving end, the image is electronically processed and supplanted to form a better image. On the sending end, similarly, the image is processed in various ways which improve the final image. This processing includes a recognition system that processes the overall image to make it look perfect. It includes text edge linearizing, and other improvements.
Another aspect of the invention is directed to security issues in facsimile machines. Often, a manager may want absolute control over all facsimiles that have been sent or received. This is one way to determine, for example, what the employees are doing or if any unauthorized communications may have been sent or received. According to the preferred machine of the present invention, all faxes, both sent and received, are stored in a non-volatile memory. Of course, only all the sent information may be stored or only all the received information may be stored.
This information is maintained in the memory, which must be nonvolatile and is preferably removable, until requested by the facsimile supervisor, using a password or a key. The fax machine allows the supervisor to either remove the media including the information (which will be in graphics format, or in one of the preferred formats of the present invention, in standard G3 or G4 form, or in some kind of compressed format) or will automatically print out all pages of the stored information.
According to another aspect of the invention, the facsimile machine includes a small camera such as a CCD camera. The CCD camera can be a low resolution, monochrome type camera, with a wide angle lens. According to this aspect of the invention, the machine acquires and stores an image of the person sending the fax as part of a package of information indicating the length of the fax and indicating where the fax was sent. Every fax that is sent has a stored image indicating who sent it.
Another aspect of this embodiment uses the CCD camera on the fax machine as above, along with an external sound pickup device attached to the fax machine, as a surveillance system. According to this aspect of the present invention, any time a noise is detected when in a surveillance mode, the CCD camera is enabled to acquire images at one second intervals. These images are converted to facsimile format and then automatically and silently sent to a specified location.
Answering machines and telephones of the prior art have sometimes had functions which allowed them to become a surveillance device. The area around the answering machine could be eavesdropped upon, after call up. This has a number of drawbacks. First, the answering machine or telephone needs to be called. This causes a ringing tone and alerts everyone to its existence. Second, sound is not enough. If a person stands still, he typically makes no sound. I, for the first time, recognized that since a fax machine sends graphics information, it could send graphic snapshots of the area as a surveillance mechanism. I also recognized that this could be done totally silently and at the direction of the monitoring machine: without the need for a polled call-in. While, of course, a call-in could be used to initiate this information, the preferred mode allows the information to be automatically sent.
When facsimile transmission was first invented, technology was still in a monochrome age. Even now, most printers are monochrome, e.g. black and white. Color printers are becoming more and more prevalent, and most offices use word processors with color screens. In the future it is believed that most printers will print in color.
Facsimile, however, lags behind this trend towards color display. The third embodiment of the present invention enables practical color faxing by disclosing a faxing machine which transmits either monochrome or color documents. This facsimile machine is intended to be used with either a scanner type facsimile system, or with a personal computer type facsimile system. For the personal computer facsimile system, the information is encoded from the color file, and is sent to the receiving facsimile machine in color. For the scanning type facsimile machine, a technique of color sensing using monochrome sensors is preferably used. These systems allow both monochrome and color faxes to be sent.
According to one aspect of this embodiment, the facsimile system "decides" whether it makes any sense to send the document in color once it determines that both the send fax and receiving fax are color capable.
According to another aspect of the present invention, the color information is encoded in a way that the monochrome system will not recognize. Therefore, a color facsimile can be sent to a monochrome machine which will ignore the color information and print only a monochrome facsimile.
The first embodiment of this invention embodied my realization that fax information which is in any case sent over a telephone line and therefore sound-based, could be stored on an audio recording medium of any type. The following embodiments require video processing capabilities, and therefore the information to be transmitted must be manipulated as a video image. Unfortunately, current techniques for storing video images, while suited for storing generalized video, are very inefficient at storage of facsimile information.
One common graphics format in which facsimile information is commonly stored is the so-called "PCX" format. This stores the facsimile as straight graphics information. An incredible amount of redundancy is present in this stored information and software compression can compress these files by 50-80%. Various compressed forms of graphics information have also been used. All these forms of information must be decompressed prior to sending.
Another storage format is shown in U.S. Pat. No. 4,491,873 which is herewith incorporated by references.
The present embodiment discloses a number of different facsimile storage formats, all of which are optimized for storing facsimile information. The storage formats are by their nature, compressed. No decompression is necessary on read-back.
Throughout this specification, the terms "facsimile" and "fax" are used interchangeably.